From ebf508e4d7635bd3f29419429c479a7313bb9e69 Mon Sep 17 00:00:00 2001 From: Andrew Ayer Date: Fri, 12 Dec 2025 10:09:22 -0500 Subject: [PATCH] Add FormatCheckpoint --- cttypes/checkpoint.go | 15 +++++++++++++++ cttypes/checkpoint_test.go | 24 ++++++++++++++++++++++++ 2 files changed, 39 insertions(+) diff --git a/cttypes/checkpoint.go b/cttypes/checkpoint.go index 2ec47be..868457b 100644 --- a/cttypes/checkpoint.go +++ b/cttypes/checkpoint.go @@ -110,3 +110,18 @@ func ParseCheckpoint(input []byte, logID LogID) (*SignedTreeHead, error) { }, nil } } + +func FormatCheckpoint(sth *SignedTreeHead, origin string, logID LogID) []byte { + keyID := makeCheckpointKeyID(origin, logID) + signature := keyID[:] + signature = binary.BigEndian.AppendUint64(signature, sth.Timestamp) + signature = append(signature, sth.Signature.Bytes()...) + + buf := new(bytes.Buffer) + fmt.Fprintln(buf, origin) + fmt.Fprintln(buf, sth.TreeSize) + fmt.Fprintln(buf, sth.RootHash.Base64String()) + fmt.Fprintln(buf) + fmt.Fprintf(buf, "\u2014 %s %s\n", origin, base64.StdEncoding.EncodeToString(signature)) + return buf.Bytes() +} diff --git a/cttypes/checkpoint_test.go b/cttypes/checkpoint_test.go index 5e4f475..1f9a286 100644 --- a/cttypes/checkpoint_test.go +++ b/cttypes/checkpoint_test.go @@ -87,3 +87,27 @@ func TestParseCheckpointFailure(t *testing.T) { } } } + +func TestFormatCheckpoint(t *testing.T) { + origin := "sycamore.ct.letsencrypt.org/2024h2" + logID := LogID{0x49, 0x4d, 0x90, 0x49, 0xb8, 0xaf, 0x3e, 0x5a, 0xca, 0xba, 0x99, 0x3e, 0x4c, 0x1f, 0x30, 0x56, 0x73, 0x7a, 0xa9, 0xf9, 0x6d, 0x00, 0xf7, 0xb0, 0xb9, 0xb2, 0x51, 0x06, 0xf7, 0xbe, 0x1a, 0x8f} + sth := SignedTreeHead{ + TreeSize: 820495916, + Timestamp: 1719511711300, + RootHash: [...]byte{0xc0, 0x3a, 0x6b, 0xe9, 0xf1, 0x1d, 0xc9, 0xcc, 0x20, 0x89, 0xe4, 0x45, 0xa7, 0x3f, 0x61, 0x41, 0xee, 0x82, 0xe8, 0x0d, 0x2d, 0x83, 0xa2, 0xb6, 0x65, 0x53, 0xd4, 0x96, 0xd7, 0x1e, 0xd2, 0x12}, + Signature: tlstypes.DigitallySigned{ + Algorithm: tlstypes.SignatureAndHashAlgorithm{ + Hash: tlstypes.SHA256, + Signature: tlstypes.ECDSA, + }, + Signature: []byte{0x30, 0x46, 0x02, 0x21, 0x00, 0xd0, 0x0d, 0x31, 0x91, 0x50, 0x80, 0x62, 0xfa, 0xb0, 0xf9, 0xf7, 0x63, 0x61, 0x78, 0x95, 0x2b, 0x9c, 0x19, 0x22, 0x3a, 0x1d, 0x08, 0xc5, 0x68, 0x0e, 0xd0, 0x8b, 0x3b, 0x79, 0x18, 0x88, 0x86, 0x02, 0x21, 0x00, 0xd5, 0x74, 0xae, 0x8c, 0x1d, 0x1d, 0x7a, 0x4e, 0x80, 0x6c, 0x36, 0x46, 0x81, 0xb4, 0x7c, 0x91, 0x78, 0xc0, 0x3f, 0xdc, 0xc0, 0xab, 0xa5, 0x90, 0x40, 0x8d, 0x0e, 0xf6, 0x2c, 0x83, 0xa9, 0x34}, + }, + } + + expected := "sycamore.ct.letsencrypt.org/2024h2\n820495916\nwDpr6fEdycwgieRFpz9hQe6C6A0tg6K2ZVPUltce0hI=\n\n\u2014 sycamore.ct.letsencrypt.org/2024h2 PdkIagAAAZBa4n5EBAMASDBGAiEA0A0xkVCAYvqw+fdjYXiVK5wZIjodCMVoDtCLO3kYiIYCIQDVdK6MHR16ToBsNkaBtHyReMA/3MCrpZBAjQ72LIOpNA==\n" + + got := FormatCheckpoint(&sth, origin, logID) + if string(got) != expected { + t.Errorf("expected %q, got %q", expected, got) + } +}